Use of (+)-a-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl) ethyl]-4-piperidinemethanol or its prodrug in the treatment of symptoms of dementia and dopamine induced psychosis

ABSTRACT

The present invention is directed to use of (+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol or its prodrug (Formula II) in treating patients for symptoms of dementia and dopamine induced psychosis.

[0001] This application is a continuation of U.S. application Ser. No.09/861,980, filed, May 18, 2001, which claims the benefit of U.S.Provisional Application No. 60/206,943, filed May 25, 2000.

[0002] Dementias are neurodegenerative diseases characterized bylearning and cognitive deficiencies and are typically accompanied bybehavioral symptoms, psychological symptoms and motor symptoms.Dementias include Alzheimer's disease, Lewy body dementia, vasculardementia, dementia in Parkinson's disease, fronto-temporal dementia,Pick's disease and corticobasal degeneration.

[0003] Alzheimer's disease, accounting for 50-60% of cases, is the mostcommon form of dementia. The second most common form was believed to bevascular dementia. Dementia with Lewy bodies (DLB) is a recentlyidentified form that may account for a substantial number of cases, andnow is proposed to be the second most common type of dementia(Pharmacotherapy (1999) 19(7): 795-803 at 795; J Neural Transm(1998)[Suppl] 54:107-116 at 107). Lewy bodies are spherical inclusionbodies seen in the brain stem nuclei of patients with Parkinson'sdisease. Recently, they were identified in cerebral and limbic corticesas well. Lewy bodies predominantly contain neurofilaments and otherproteins such as ubiquitin. The origin of their development is unknown.

[0004] Alzheimer's disease and DLB can be distinguished at the molecularlevel and through clinical observation. Alzheimer's disease ischaracterized by deposits of amyloid protein and hyperphosphorylation ofthe microtubular associated protein tau, and DLB by neurofilamentabnormalities including phosphorylation, ubiquitination, proteolysis,and cross-linking of constitutent proteins. The two diseases appeartherefore to be distinct at an ultrastructural and molecular level, aconclusion which is consistent with the fact that the clinical syndromesassociated with DLB and Alzheimer's disease are sufficientlydifferentiated to allow for accurate antemortem diagnosis (J NeuralTransm (1998)[Suppl] 54:107-116 at 107).

[0005] The presence of psychopathology early in the disease coursedistinguishes DLB from other dementias (Am J Psychiatry 156(7):1039-45). The Parkinsonian motor features are typically mild,spontaneous features such as bradykinesia and rigidity. Masked faces,hypophonia and a slow shuffling gait are also common. Patients treatedwith levodopa respond poorly and the drug can exacerbate or causehallucinations (Pharmacotherapy 1999: 19(7) 795-803 at 796).

[0006] Patients with Parkinson's disease often develop dementia as thedisease progresses, and hallucinations are a common side effect oflevodopa therapy (“dopamine induced psychosis”). If the onsets ofdementia and Parkinson's symptoms occur within 12 months of each other,a diagnosis of DLB can be made. The symptoms of myoclonus, absence ofrest tremor, lack of response to levodopa, or no perceived need toadminister levodopa are 10 times more likely in DLB than in Parkinson'sdisease Id. at 798. Since the compounds of the present invention havevery little activity at the dopamine receptor (unlike some other5HT_(2A) antagonists), these compounds are useful in treating patientssusceptible to dopamine induced psychosis.

[0007] Increased sensitivity to neuroleptic agents is another importantindicator in DLB and has significant pharmacotherapeutic implications.Many patients require neuroleptics to treat psychotic symptoms, butneuroleptics can exacerbate the parkinsonian symptoms (extrapyramidalsymptoms, “EPS”) in DLB. Therefore, neuroleptics in DLB must beprescribed with caution, if at all. Id. at 796. The compounds of thepresent invention do not exacerbate EPS.

[0008] The combination of the sensitivity to neuroleptic agents, the ageand condition of the patient, and the symptoms manifested in DLB producea quandary for the physician in prescribing medication. There have beenmany suggestions for therapy published, but all therapies have hadlimited or mixed success.

[0009] Pick's disease is a dementing disorder primarily involving thefrontal and temporal lobes. It is characterized clinically by aninsidious mid-life onset (50-65 years of age) of personality andbehavioral changes, disinhibition, impairment of language function anddecline in memory and intellect. NEUROPATHY OF DEMENTING DISORDERS, Wm.R. Markesberry, MD, editor, Arnold, Hodder Headline.

[0010] Fronto-Temperoral dementia is a dementing disorder characterizedby degeneration of the frontal and anterior temporal lobe.

[0011] Corticobasal degeneration is a dementing disorder which ispredominantly an extrapyramidal motor disorder.

[0012] It is an object of the present invention to treat symptoms ofdementias. Such symptoms include:

[0013] a) Behavioral symptoms such as sleep disturbances, delirium(including fluctuations), aggression and agitation;

[0014] b) Psychological symptoms such as hallucinations, delusions,anxiety and depression;

[0015] c) Motor symptoms which means impaired ability to carry out motoractivities despite intact motor function; and

[0016] d) Learning and cognitive impairment, for example, impairedability to learn new information or to recall previously learnedinformation (e.g., impaired social memory), aphasia, apraxia, agnosia,disturbance in executive functioning, etc.

[0017] It is also an object of the present invention to treat dopamineinduced psychosis. Another object is to treat patients for dementia, ordopamine induced psychosis having Parkinson's disease or DLB, withoutexacerbating or creating EPS or dopamine induced psychosis.

[0018] A compound of the present invention,(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol,or its pharmaceutically acceptable salt, is a potent antagonist at theserotonin 5HT_(2A) receptor (J. Pharm. Exp. Ther. (1996) 277:968-9881)incorporated herein by reference. It was described in U.S. Pat. No.5,134,149, incorporated herein by reference.

[0019] Other compounds of the present invention include prodrugs of(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol,or its pharmaceutically acceptable salt, which mean that a compound isadministered which is different from(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolbut(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolbecomes available in the body after metabolism. As used herein,“prodrug” has the specific meaning of the compounds disclosed in U.S.Pat. No. 6,028,083, incorporated herein by reference, shown hereafter asFormula II:

[0020] wherein R is C₁-C₂₀ alkyl, or a stereoisomer or apharmaceutically acceptable salt thereof. “Alkyl” means a branched orstraight chain alkyl group specified by the amount of carbons in thealkyl group, e.g., C₁-C₂₀ alkyl means one, two, three, four, five, six,seven, eight, nine, ten eleven, twelve, thirteen, fourteen, fifteen,sixteen, seventeen, eighteen, nineteen, or twenty carbon branched orstraight chain alkyl or ranges thereof, for example, but not limited toC₁-C₁₅, C₅-C₂₀, C₃-C₁₅, C₅-C₁₅, C₇-C₁₅ and C₇ to C₉.

[0021](+)-α-(2,3-Dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolantagonizes the effects of serotonin at the 5HT_(2A) receptor and thusis useful for treating a variety of conditions. Some of the uses for(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolhave been disclosed in patents and patent applications. U.S. Pat. No.5,169,096 claimed compounds having a generic scope which encompassed the(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanoland disclosed uses of the treatment of anorexia nervosa, variant angina,Raynaud's phenomenon, coronary vasospasms, prophylactic treatment ofmigraine, cardiovascular diseases such as hypertension, peripheralvascular disease, thrombotic episodes, cardiopulmonary emergencies andarrythmias, and has anesthetic properties. See also U.S. Pat. Nos.4,783,471; 4,912,117; and 5,021,428, which are divisions of U.S. Pat.No. 5,169,096. See also U.S. Pat. No. 4,877,798 (fibromyalgia), U.S.Pat. No. 4,908,369 (insomnia); U.S. Pat. No. 5,106,855 (glaucoma); U.S.Pat. No. 6,004,980 (anxiety, Raynauds phenomenon, cardiac arrhythmia;extrapyramidal symptoms; drug abuse, anorexia, fibromylagia). All of theforegoing are incorporated herein by reference.

[0022] The(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolwas then specifically claimed in U.S. Pat. No. 5,134,149 which discloseduses of antagonizing serotonin at the 5HT2 receptor, treating anxiety,variant angina, anorexia nervosa, Raynaud's phenomenon, intermittentclaudication, coronary or peripheral vasospasms, fibromyalgia,extrapyramidal symptoms, arrythmias, thrombotic illness, transientischemic attacks, drug abuse, and psychotic illness such asschizophrenia and mania. See also U.S. Pat. Nos. 5,561,144; 5,700,812;5,700,813; 5,721,249—divisionals of U.S. Pat. No. 5,134,149—and alsoU.S. Pat. No. 5,618,824 (obsessive compulsive disorder) andPCT/US97/02597 (depressive disorders including major depressive episodeand dysthymia, and bipolar disorder), and insomnia and sleep apnea,incorporated herein by reference.

DETAILED DESCRIPTION OF THE INVENTION

[0023] Terms used herein have the meanings defined here and elsewhere inthis specification.

[0024] a) “Pharmaceutically acceptable salts” means either an acidaddition salt or a basic addition salt, whichever is possible to makewith the compounds of the present invention.

[0025] “Pharmaceutically acceptable acid addition salt” is any non-toxicorganic or inorganic acid addition salt of the base compoundsrepresented by Formula I. Illustrative inorganic acids which formsuitable salts include hydrochloric, hydrobromic, sulfuric andphosphoric acid and acid metal salts such as sodium monohydrogenorthophosphate and potassium hydrogen sulfate. Illustrative organicacids which form suitable salts include the mono-, di- andtri-carboxylic acids. Illustrative of such acids are, for example,acetic, glycolic, lactic, pyruvic, malonic, succinic, glutaric, fumaric,malic, tartaric, citric, ascorbic, maleic, hydroxymaleic, benzoic,hydroxybenzoic, phenylacetic, cinnamic, salicyclic, 2-phenoxybenzoic,p-toluenesulfonic acid and sulfonic acids such as methanesulfonic acidand 2-hydroxyethanesulfonic acid. Either the mono- or di-acid salts canbe formed, and such salts can exist in either a hydrated orsubstantially anhydrous form. In general, the acid addition salts ofthese compounds are more soluble in water and various hydrophilicorganic solvents and which in comparison to their free base forms,generally demonstrate higher melting points.

[0026] “Pharmaceutically acceptable basic addition salts” meansnon-toxic organic or inorganic basic addition salts of the compounds ofFormula (I) or any of its intermediates. Examples are alkali metal oralkaline-earth metal hydroxides such as sodium, potassium, calcium,magnesium or barium hydroxides; ammonia, and aliphatic, alicyclic, oraromatic organic amines such as methylamine, trimethylamine andpicoline. The selection of the appropriate salt may be important so thatthe ester is not hydrolyzed. The selection criteria for the appropriatesalt will be known to one skilled in the art.

[0027] b) “Patient” means a warm blooded animal, such as for examplerat, mice, dogs, cats, guinea pigs, and primates such as humans.

[0028] c) “Treat” or “treating” means to alleviate symptoms, eliminatethe causation of the symptoms either on a temporary or permanent basis,or to prevent or slow the appearance of symptoms of the named disorderor condition.

[0029] d) “Therapeutically effective amount” means an amount of thecompound which is effective in treating the named disorder or condition.

[0030] e) “Pharmaceutically acceptable carrier” is a non-toxic solvent,dispersant, excipient, adjuvant or other material which is mixed withthe compound of the present invention in order to permit the formationof a pharmaceutical composition, i.e., a dosage form capable ofadministration to the patient. One example of such a carrier is apharmaceutically acceptable oil typically used for parenteraladministration.

[0031] f) “Sleep Disturbances” means fragmented sleep, narcolepsy and“REM” or “Rapid Eye Movement” behavior disorder, restless legs and/orperiodic limb movements.

[0032] g) “EPS” or “Extrapyramidal symptoms” are symptoms which maymanifest upon administration of neuroleptic drugs. The symptoms includea parkinsonian-like syndrome wherein the patient experiences muscularrigidity and tremors. Some experience akathesia and acute dystonicreactions.

[0033] h) “Stereoisomers” is a general term for all isomers of theindividual molecules that differ only in the orientation of their atomsin space. It includes mirror image isomers (enantiomers), geometric(cis/trans) isomers, and isomers of compounds with more than one chiralcenter that are not mirror images of one another (diastereoisomers).

[0034] i) M100907 means (+)-isomer ofα-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol.

[0035] The (+)-isomer ofα-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolcan be prepared by methods described in U.S. Pat. No. 5,134,149. Onesuitable method follows.

[0036] In Step A of Reaction Scheme I, an esterification reaction iscarried out between racemicalpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol(structure 1) and the (+)-isomer of alphamethoxyphenylacetic acid(structure 2). This esterification produces the diastereomeric mixtureidentified as structure 3. These diastereomers are subjected to silicagel chromatography which separates the two diastereomers, therebyisolating the (+,+) diastereomer as is depicted in Step B. In Step C,the (+,+) diastereomer is hydrolyzed which produces the (+)-isomer ofalpha(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol.

[0037] The esterification reaction can be carried out using techniquesknown in the art. Typically approximately equivalent amounts of racemicalpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanoland the (+)-isomer of alpha-methoxyphenylacetic acid are contacted in anorganic solvent such as methylene chloride, THF, chloroform, or tolueneand heated to reflux for a period of time ranging from 5 to 24 hours.The esterification is typically carried out in the presence of anequivalent amount of dicyclohexylcarbodiimide (DCC) and a catalyticamount of 4-dimethylaminopyridine (DMAP). The resulting diastereomerscan be isolated by filtration of the dicyclohexylurea and evaporation ofthe filtrate.

[0038] The diastereomers are then subjected to silica gel chromatographywhich separates the (+,+) and the (−,+) diastereomers. Thischromatographic separation may be carried out as is known in the art. A1:1 mixture of hexane and ethyl acetate is one suitable eluent.

[0039] The resulting (+,+) diastereomer is then subjected to ahydrolysis reaction which produces the (+)-enantiomer ofalpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol.The hydrolysis is carried out by contacting the diastereomer with anexcess of a base such as potassium carbonate in an aqueous alcoholicsolution. The hydrolysis is carried out at a temperature of about 15 to30° C. for a period of time ranging from 2 to 24 hours. The resulting(+)-isomer ofalpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolmay then be recovered by dilution with water and extraction withmethylene chloride. It is then purified by recrystallization from asolvent system such as cyclohexane/hexane or ethyl acetate/hexane.

[0040] Methods for producing the starting materials of Reaction Scheme Iare known in the art. For example, U.S. Pat. No. 4,783,471 teaches howto prepare racemicalpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol.This patent is hereby incorporated by reference. Examples No. 1 and 2 ofthis application also teach suitable methods. Alternatively, racemicalpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolcan be prepared in the following manner. Initially 4-hydroxypiperidineis subjected to an N-alkylation reaction with p-fluorophenylethylbromide which produces 4-hydroxy-1-[2-(4-fluorophenyl)ethyl]-piperidine.This compound is brominated with Ph₃P.Br₂ which produces4-bromo-1-[2-(4-fluorophenyl)ethyl]piperidine. This compound iscontacted with Mg thereby forming a Grignard Reagent which is thenreacted with 2,3-dimethoxybenzaldehyde which produces the desiredproduct(±)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol.The (+)-isomer of alphamethoxyphenylacetic acid is known in the art.

[0041] Scheme II shows the synthesis of the compounds of Formula II,Prodrugs.

[0042] Referring to Scheme II, X is chloro or bromo, with chloro beingpreferred and R is as previously defined. This reaction scheme shows themaking of the sustained release compounds of Formula I from the alcohol(5).

[0043] The alcohol (5) is reacted with an acid halide (RC(O)X), RCO₂H oracid anhydride (RCO)₂O in the presence of an a sufficient amount of anappropriate base. An appropriate base is one that permits esterformation from the acid halide or anhydride. Examples of appropriatebases are trialkylamines, pyridine such as dimethylamino pyridine,diisopropyl ethyl amines, N-methyl morpholines, with triethylamine beingpreferred. A sufficient amount of the base can be ascertained by oneskilled in the art which permits the formation of the compounds ofFormula I.

[0044] Preferably the base is added to the alcohol (5) and that mixtureadded dropwise to the acid halide or acid anhydride in an appropriatesolvent. Examples of appropriate solvents are chloroform, methylenechloride, or toluene, all of which are readily available, withchloroform being preferred.

[0045] The temperature of the reaction may be at a range of about 0-25°C. The reaction mixture may be stirred for from a few hours to overnightto enhance the reaction. Catalysts may also be added for enhancement ofreaction times, e.g., 4-dimethylaminopyridine or the like.

[0046] The starting materials for the acid halide (RCOX) are readilyavailable for those skilled in the art. For example, Aldrich Chemicalcompany provides stearoyl chloride, heptadecanoyl chloride, palmitoylchloride, myristoyl chloride, isovaleryl chloride, valeryl chloride,hexanoyl chloride, hexanoyl chloride, heptanoyl chloride, octanoylchloride, nonanoyl chloride, decanoyl chloride, undecanoyl chloride andlauroyl chloride. For those acid halides not readily available, oneskilled in the art may prepare the acid halide desired. For example, acarboxylic acid may be mixed with a halide donor to produce the desiredacid halide. One example of this is to mix carboxylic acid (0.17 mol),methylene chloride (660 mL) and dimethylformamide (0.5 mL) under anitrogen atmosphere. Add oxalyl chloride (0.2 mol) over about 5 minuteswith stirring. Stir at ambient temperature for 3 hours and evaporate thesolvent in vacuo to the acid chloride. Another method is to dissolve thecarboxylic acid (10 mmol) in methylene chloride (50 mL). Cool to 0° C.,place under a nitrogen atmosphere and add, by dropwise addition, thionylchloride (11 mmol). Stir at room temperature for several hours andevaporate the volatiles in vacuo to give the acid chloride. Thecarboxylic acids are readily available or can be easily made by thoseskilled in the art.

[0047] The starting materials for the acid anhydrides (RCO)₂O arereadily available for those skilled in the art. For example, AldrichChemical company provides butryic anhydride, isobutyric anhydride,valeric anhydride, 2-2,dimethylglutaric anhydride, and phthalicanhydride. Alternatively, acid anhydrides may be synthesized by methodswell known in the art.

[0048] The starting materials for the acids (RCO₂H) are readilyavailable or may be synthesized by methods well know in the art. Forexample, see Advanced Organic Chemistry, Reactions, Mechanisms, andStructure, 4th ed., John Wiley & Sons, New York 1992, incorporatedherein by reference. Aldrich Chemical Company also provides isovalericacid, valeric acid, tert-butylacetic acid, 2,2dimethylbutyric acid,2-ethylbutyric acid, hexanoic acid, 3-methylvaleric acid,4-methylvaleric acid, heptanoic acid, octanoic acid, 2-propylpentanoicacid, nanoic acid, decanoic acid, undecanoic acid, lauric acid,tridecanoic acid, myristoleic acid, myristic acid, pentadecanoic acid,palmitic acid, heptadecanoic acid, stearic acid, nonadecanoic acid,eicosanoic acid.

[0049] The following examples are being present to further illustratethe invention. However, they should not be construed as limiting theinvention in any manner.

EXAMPLE 1 Starting Material

[0050] Example 1, Steps A-D, demonstrates the preparation of thestarting material(±)-alpha(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol,structure 1, Scheme I.

[0051] A) 1-[2-(4-Fluorophenyl)ethyl]-4-piperidinecarboxamide

[0052] A solution of isonipecotamide (10.9 g, 85.0 mmol),2-(4-fluorophenyl)ethyl bromide (15.7 g, 77.3 mmol), and K₂CO₃ (2.3 g,167 mmol) was prepared in DMF (280 mL) and stirred under argon at 90-95°C. overnight. The cooled solution was concentrated to a white oilysolid. The solid was partitioned between water and CH₂Cl₂. The layerswere separated and the aqueous layer was extracted with CH₂Cl₂. Thecombined organic layers were washed 2× with water, dried (MgSO₄),filtered, and evaporated to a oily solid. The solid was recrystallizedfrom EtOAc to afford 1-[2-(4-fluorophenyl)ethyl]-4-piperidinecarboxamideas a white powder, m.p. 177-178° C. (decomp.). Anal. Calcd forC₁₄H₁₉FN₂O: C, 67.18; H, 7.65; N, 11.19. Found: C, 67.25; H, 7.67; N,11.13.

[0053] B) 4-Cyano-1-[2-(4-fluorophenyl)ethyl]piperidine

[0054] To stirred phosphorus oxychloride (25 mL, 41.12 g, 268 mmol) andsodium chloride (5.1 g, 87.3 mmol) was added1-[2-(4-fluorophenyl)ethyl]-4-piperidinecarboxamide (8.9 g, 35.6 mmol)portionwise. After complete addition, the solution was refluxed for 2hours. The cooled solution was carefully poured into dilute NH₄OH todestroy the POCl₃. The aqueous solution was cooled to 0° C., thenextracted 2× with CH₂Cl₂. The combined organic layers were dried(MgSO₄), filtered, and evaporated to afford 8.1 g of an oily solid. Thesolid was distilled, (b.p. 150° C., 0.1 mm Hg), to afford a clear,colorless oil that solidified. This material was crystallized fromhexane to afford 4-cyano-1-[2-(4-fluorophenyl)ethyl]piperidine as whiteneedles, m.p. 47-48° C. Anal. Calcd for C₁₄H₁₇FN₂: C, 72.39; H, 7.38; N,12.06. Found: C, 72.62; H, 7.49; N, 12.12.

[0055] C) 1-[2-(4-Fluorophenyl)ethyl]-4-piperidinecarboxaldehyde

[0056] To a stirred solution of4-cyano-1-[2-(4-fluorophenyl)-ethyl]piperidine (1.00 g, 4.3 mmol) in THF(20 mL) under argon at 0° C. was added DIBAL-H (4.6 mL of a 1.0 Msolution in THF, 4.6 mmol) via syringe. After stirring overnight at roomtemperature, 10% aqueous HCl (25 mL) was added and the solution wasstirred for 3 hours. The entire mixture was then poured into 10% aqueousNaOH (50 mL), then extracted 2× with ether. The combined organic layerswere washed with brine, dried (MgSO₄), filtered, and evaporated toafford a pale yellow oil. The oil was chromatographed on silica gel,eluting with EtOAc. The appropriate fractions were combined andevaporated to afford an oil. This oil was distilled (b.p. 166° C., 0.05mm Hg) to afford 1-[2-(4-fluorophenyl)ethyl]-4-piperidinecarboxaldehyde,obtained as a colorless oil. Anal. Calcd for C₁₄H₁₈FNO: C, 71.46; H,7.71; N, 5.95. Found: C, 71.08, H, 7.81; N, 5.86.

[0057] D)(±)-alpha(2,3-Dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol

[0058] To a stirred solution of veratrole (0.93 g, 6.7 mmol) in THF (20mL) under argon at 0° C. was added n-BuLi (2.7 mL of a 2.5 M solution inhexane, 6.75 mmol). After stirring 2.5 h, the solution was cooled to−78° C. and treated with1-[2-(4-fluorophenyl)ethyl]-4-piperidinecarboxaldehyde (1.30 g, 5.5mmol) in THF (25 mL) via an addition funnel. The cooling bath wasremoved and the solution was allowed to stir for 2 hours. Water wasadded, the layers separated, and the aqueous layer was extracted withEtOAc. The combined organic layers were washed with brine, dried(MgSO₄), filtered, and chromatographed on silica gel, eluting withacetone. The appropriate fractions were combined and evaporated toafford a white solid. The solid was recrystallized from hexane to affordracemicalpha(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolas shiny white needles, m.p. 126-127° C. Anal. Calcd for C₂₂H₂₈FNO₃: C,70.75; H, 7.56; N, 3.75. Found: C, 70.87; H, 7.65; N, 3.68.

EXAMPLE 2 Starting Material

[0059] Example 2, Steps A-F, demonstrate an alternative manner ofpreparing(±)-alpha(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)-ethyl]-4-piperidinemethanol,structure 1.

[0060] A) 1-(1,1-Dimethylethyl)-1,4-piperidinedicarboxylic Acid

[0061] To isonipecotic acid (107.5 g, 832 mmol) stirred in 1N NaOH (40 gNaOH in 900 mL H₂O) and tert-butanol (1800 mL) was added di-tert-butyldicarbonate (200 g, 916 mmol) in portions. After stirring overnight, thesolution was concentrated and the resulting water layer was acidifiedwith aqueous HCl. This acidic aqueous layer was extracted 3× with ether.The combined organic layers were washed with water, brine, dried(MgSO₄), filtered, and evaporated to a white solid, which wasrecrystallized from EtOAc/hexane (300 mL/200 mL) to afford1-(1,1-dimethylethyl)-1,4-piperidinedicarboxylic acid as white needles,m.p. 147-149° C.

[0062] B) 4-(N-Methoxy-N-methylcarboxamido)-1-piperidinecarboxylic Acid1,1-dimethylethyl Ester

[0063] To a stirred solution of1-(1,1-dimethylethyl)-1,4-piperidinedicarboxylic acid (50.0 g, 218 mmol)in anhydrous CH₂Cl₂ (500 mL) under N₂ in a 2L flask was added1,1′-carbonyldiimidazole (38.9 g, 240 mmol) portionwise. After stirringfor 1 hour, N,O-dimethylhydroxylamine hydrochloride (23.4 g, 240 mmol)was added in one portion. After stirring overnight, the solution waswashed twice with 1N HCl, twice with saturated NaHCO₃, once with brine,dried (MgSO₄), filtered, and evaporated to an oil. Distillation afforded4-(N-methoxy-N-methylcarboxamido)-1-piperidinecarboxylic acid1,1-dimethylethyl ester as a clear oil, b.p. 120-140° C., 0.8 mm.

[0064] C) 4-(2,3-Dimethoxybenzoyl)-1-piperidinecarboxylic Acid1,1-dimethylethyl Ester

[0065] n-Butyl lithium (14.5 mL of a 2.5 M solution in hexane, 36.3mmol) was added via syringe to a stirred solution of veratrole (5.00 g,36.2 mmol) in THF (50 mL, anhydrous) under argon at 0° C. The ice bathwas removed and the mixture was allowed to stir for 90 minutes. Themixture was cooled to −78° C. and treated with4-(N-methoxy-N-methylcarboxamido)-1-piperidinecarboxylic acid1,1-dimethylethyl ester (9.20 g, 33.8 mmol) in THF (50 mL, anhydrous)via syringe. The cooling dry ice-acetone bath was removed and themixture was allowed to come to room temperature. After stirring for 3hours, saturated aqueous NH₄Cl was added and the mixture was allowed tostir overnight. The layers were separated and the aqueous layer wasextracted with ether. The combined organic layers were washed withbrine, dried (MgSO₄), filtered, and evaporated to afford an amber oil.The oil was chromatographed on silica gel, eluting with 20% EtOAc inhexane. The appropriate fractions were combined and evaporated to anamber oil. The oil was distilled to afford4-(2,3-dimethoxybenzoyl)-1-piperidinecarboxylic acid 1,1-dimethylethylester as a colorless oil.(b.p. 225-250° C., 0.05 mm). Anal. Calcd forC₁₉H₂₇NO₅: C, 65.31; H, 7.79; N, 4.01. Found: C, 65.04; H, 7.92; N,4.11.

[0066] D) 4-(2,3-Dimethoxyphenyl)-4-piperidinylmethanone

[0067] 4-(2,3-Dimethoxybenzoyl)-1-piperidinecarboxylic acid1,1-dimethylethyl ester (7.75 g, 22.2 mmol) was dissolved intrifluoroacetic acid (50 mL, 650 mmol) and stirred for 45 minutes. Theentire solution was poured into ether (900 mL) and allowed to standovernight. Filtration yielded4-(2,3-dimethoxyphenyl)-4-piperidinylmethanone trifluoroacetate as finewhite needles, m.p. 123° C. Anal. Calcd for C₁₄H₁₉NO₃.CF₃CO₂H: C, 52.89;H, 5.55; N, 3.86. Found: C, 52.77; H, 5.62; N, 3.82.

[0068] The resulting 4-(2,3-dimethoxyphenyl)-4-piperidinylmethanonetrifluoroacetate was dissolved in water, treated with NaOH (10% aqueous)until basic, and extracted three times with dichloromethane. Thecombined organic layers were washed with brine, dried (MgSO₄), filtered,and evaporated to afford 4-(2,3-dimethoxyphenyl)-4-piperidinylmethanoneas an oil.

[0069] E)(2,3-Dimethoxyphenyl)[1-[2-(4-fluorophenyl)ethyl]-4-piperidinyl]methanoneMonohydrochloride

[0070] A solution of 4-(2,3-dimethoxyphenyl)-4-piperidinylmethanone(8.00 g, 32.1 mmol) and 2-(4-fluorophenyl)ethyl bromide (6.52 g, 32.1mmol) was prepared in DMF (90 mL), treated with K₂CO₃ (7.0 g, 50.7mmol), then stirred and heated at 80° C. under argon overnight. Thecooled solution was poured into a partition of 2/1 EtOAc/toluene andwater. The layers were separated and the aqueous layer was extractedwith 2/1 EtOAc/toluene. The combined organic layers were washed 2× withwater, 1× with brine, dried (MgSO₄), filtered, and evaporated to afford11.0 g of an oil. The oil was chromatographed on silica gel, elutingwith EtOAc. The appropriate fractions were combined, concentrated,dissolved in ethyl acetate and treated with HCl/ethyl acetate.(2,3-dimethoxyphenyl)[1-[2-(4-fluorophenyl)ethyl]-4-piperidinyl]-methanonemonohydrochloride was obtained as a precipitate, m.p. 225-227° C.(decomp). Anal Calcd for C₂₂H₂₆FNO₃.HCl: C, 64.78; H, 6.67; N, 3.43.Found: C, 64.44; H, 6.73; N, 3.41.

[0071] F)(±)-alpha-(2,3-Dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol

[0072] To a stirred solution of(2,3-dimethoxyphenyl)[1-[2-(4-fluorophenyl)ethyl]-4-piperidinyl]methanone(6.0 g, 16.2 mmol) in MeOH (100 mL) at 0° C. was added NaBH₄ (1240 mg,32.8 mmol) in two portions, over a one hour period. After stirringovernight, the solution was concentrated to a solid. The solid waspartitioned between water and ether. The layers were separated and theaqueous layer was extracted with ether. The combined organic layers werewashed with brine, dried (MgSO₄), filtered, and evaporated to a solid.The solid was chromatographed on silica gel, eluting with acetone. Theappropriate fractions were combined and evaporated to afford a whitesolid. The solid was recrystallized from cyclohexane to afford(±)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)-ethyl]-4-piperidinemethanolas white needles, m.p. 126-127° C.

[0073] Anal. Calcd for C₂₂H₂₈FNO₃: C, 70.75; H, 7.56; N, 3.75.

[0074] Found: C, 70.86; H, 7.72; N, 3.93.

EXAMPLE 3 Starting Material

[0075] This example demonstrates the preparation of the alcohol,structure 5.

[0076] Preparation of(+)-alpha-(2,3-Dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol

[0077] A) Preparation of Diastereomers.

[0078] A solution of 3.90 g (10.4 mmol) of(±)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol,1.74 g (10.4 mmol) of S-(+)-alpha-methoxyphenylacetic acid, 2.15 g (10.4mmol) of 1,3-dicyclohexylcarbodiimide and 0.1 g of4-dimethylaminopyridine in chloroform (75 mL) was refluxed for 17 hours,allowed to cool to room temperature and filtered. The filtrate wasconcentrated and chromatographed on a silica gel column eluting withethyl acetate/hexane (1:1) to afford two diastereomers, Rf=0.1 and 0.2(TLC EtOAc/hexane, 1:1). Intermediate fractions were rechromatographedto give additional material. Those fractions with Rf=0.2 were combinedto give a single diastereomeric ester,(+,+)-(2,3-dimethoxyphenyl)[1-[2-(4-fluorophenyl)ethyl]-4-piperidinyl]methyl-alpha-methoxybenzeneacetate.

[0079] B) Preparation of(+)-alpha-(2,3-Dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol

[0080] To a stirred solution of 0.97 g (1.9 mmol) of the above mentioneddiastereomeric ester, Rf=0.2, in 25 mL of methanol was added 0.5 g (3.6mmol) of potassium carbonate and 5.0 mL of water. After stirring 17hours at room temperature the reaction mixture was diluted with waterand extracted twice with methylene chloride. The combined extracts werewashed with water, brine and dried over MgSO₄. After filtering, thefiltrate was concentrated to an oil and crystallized from 40 mL ofcyclohexane/hexane (1:1) to give(+)-alpha-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol,m.p. 112-113° C., [α]_(D) ²⁰=+13.9°.

EXAMPLE 4

[0081] The compound of the present invention can be shown to beeffective by clinical trials in humans and certain behavioral tests inanimals.

[0082] Examples of methods in human clinical trials follow.

[0083] 1. Bristol Activities of Daily Living Scale, Bucks, Ashworth,Wilcock Siegfried 1996 (incorporated herein by reference). The patientis observed and rated according to their ability to perform certainfunctions such as the ability to prepare food, eat, drink, dress, shop,communicate, etc., i.e., the ability to perform normal daily functionsand to be appropriately oriented to time and space.

[0084] 2. Senile Dementia Associated Sleep Disorder (SDASD), Cacabelos,Laredo, Couceiro, Alvarez 1999(incorporated herein by reference).Conditions are noted for sleep disturbances such as initial insomnia,nocturnal sleep disruption, delayed insomnia, fragmented sleep patterns,etc.

[0085] 3. Cornell Scale for Depression in Dementia., Alexopoulos,Abrams, Young, Shamoian 1988 (incorporated herein by reference). Moodrelated signs, behavioral disturbances, physical signs, cyclic functionsand ideational disturbances are noted and rated.

[0086] 4. Cognitive Assessment Systems, e.g., Learning and Motivation 4:327-342; International Journal of Geriatric Psychiatry 10: 189-201(incorporated herein by reference). Patient is rated on their ability torecognize words, pictures, etc.

[0087] 5. Unified Parkinson's Disease Rating Scale (UPDRS), Langston,Widner, Goetz, Brooks, Fahn, Freeman, Watts 1992). The patient isobserved for typical motor and gait symptoms present in Parkinsons.

[0088] 6. Hallucinations/Delusions. The patient is interviewed andobserved regarding hallucinations and delusions and rated according toset protocol.

[0089] 7. Polysomnography to study increase in slow wave sleep.

EXAMPLE 5

[0090] Administration of scopolamine, an antagonist at the acetylcholinemuscarinic receptor, has been associated with hallucinations andbehavioral disturbances in humans (Brain and Cognition (1995)28:240-258). Also, scopolamine-induced hyperlocomotion in the rat hasbeen used as a model of behavioral disturbances related to cholinergicdeficiency states (Jpn J Pharmacol (1999) 79 (Suppl. 1):43P).Cholinergic deficiency states include various neurodegenerative diseasessuch as Alzheimer's Disease, Dementia with Lewy Bodies, Charles BonnetSyndrome, delirium and Parkinson's Disease.

[0091] Experimental Procedure. All procedures were conducted in normalwhite light conditions. Rats (1 per box) were first acclimated to testboxes (45×22×20 cm; clear polycarbonate with a plastic top) for 90minutes. Each rat was then given two intraperitoneal injections(vehicle+vehicle, vehicle+scopolamine, test compound dose 1+scopolamine,test compound dose 2+scopolamine, test compound dose 3+scopolamine ortest compound dose 4+scopolamine) and replaced into its test box, whichwas placed into an activity counter (Opto-Varimex Mini, ColumbusInstruments, Columbus, Ohio). Testing commenced immediately. Locomotoractivity was recorded for 60 min in the activity counter, which wasequipped with 15 photoelectric light sources spaced at 2 cm intervalsand 1 cm above the floor. Each interruption of a photoelectric lightbeam was recorded as a single activity count by a microprocessor-basedcontrol system. Testing took place between 10:00 a.m. and 5:00 p.m.,with all groups counterbalanced for time of testing. The experimenterwas blind to treatment group during the experiment.

[0092] Results. M100907 (0.03-1 mg/kg) and risperidone (0.03-1 mg/kg)significantly antagonized scopolamine-stimulated locomotion (see FIGS.1-2 and Tables 1-2; Abbreviations: VEH=vehicle, SCOP=scopolamine).M100907 restored activity to baseline (vehicle) level, but risperidoneat the two higher doses reduced activity below baseline level.

[0093] Conclusions. The present results demonstrate that the selective5-HT2A antagonist M100907 antagonized scopolamine-stimulated locomotionin rats without reducing activity levels below baseline. The⁵-HT_(2A)/D₂ antagonist risperidone also antagonizedscopolamine-stimulated locomotion, but the two higher doses reducedactivity levels below baseline. This could be due to risperidone'spotent D₂ antagonist activity, which may have resulted in sedation ormotor dysfunction. TABLE 1 M100907: Group means of 60 min activity counttotals +/− SEM Treatment n MEAN +/− SEM VEH + VEH 6 1687  457 VEH + SCOP0.75 6 5753 1386 # M100907 0.03 + SCOP 0.75 6 3181  804 * M100907 0.1 +SCOP 0.75 6 2378  306 * M100907 0.3 + SCOP 0.75 6 2087  752 * M1009071 + SCOP 0.75 6 2231  737 *

[0094] TABLE 2 Risperidone: Group means of 60 min activity count totals+/− SEM Treatment n MEAN +/− SEM VEH + VEH 8 2484  441 VEH + SCOP 0.75 87975 1880 ## RISPERIDONE 0.03 + SCOP 0.75 8 4615 1382 * RISPERIDONE0.1 + SCOP 0.75 8 4037 1156 * RISPERIDONE 0.3 + SCOP 0.75 8 1795  336 **RISPERIDONE 1 + SCOP 0.75 8  772  203 ***

EXAMPLE 6

[0095] M100907 (0.1 and 1 mg/kg) significantly enhanced social memory inmice. Male CD-1 mice (30-35 grams) were first acclimated to the testroom for approximately 1 hour. The mice were then administered vehicleor M100907 (0.01, 0.1 or 1 mg/kg p.o.) 2 hours prior to their baselinetest. For the baseline test, unfamiliar pairs of mice were placed into atest chamber (plexiglas mouse cage with sawdust bedding). The durationof social interaction of the two mice (sniffing, anogenital exploration,nosing, grooming, licking, pawing, playing copulatory attempts) wasobserved and recorded for a period of five minutes and was registeredcumulatively as total seconds of contact. Twenty-four hours later, theanimals were given a retest without any drug treatment. At the retest,the now familiar partners from the baseline test were placed into thetest chamber for a second confrontation and the duration of socialinteraction was again measured. Social memory was defined as asignificant decrease in duration of social contact from baseline toretest. Testing took place in normal white light conditions between thehours of 8:30 am and 3:00 pm. The experimenter was blind to thetreatment group until the completion of the experiment. The resultsrepresent combined data (n=36 per group total) from two studies. Datawere analyzed using the Mann-Whitney test. TABLE 3 Treatment n MEAN +/−SEM VEH (baseline) 36 25.82 2.03 VEH (retest) 36 23.88 1.82 M100907 0.01(baseline) 36 23.05 1.28 M100907 0.01 (retest) 36 20.3 1.41 M100907 0.1(baseline) 36 25.5 2.0 M100907 0.1 (retest) 36 21.21 1.57* M100907 1(baseline) 36 25.0 1.89 M100907 1 (retest) 36 18.1 1.47*

[0096] The dosage range at which the compounds of Formula I exhibittheir ability treat patients with DLB depends upon the severity of thedisease, the patient, the formulation, other underlying disease statesthat the patient is suffering from, and other medications that may beconcurrently administered to the patient. Generally, the compounds ofFormula I will exhibit their therapeutic activities between about 0.001mg/kg of patient body weight/day to about 100 mg/kg of patient bodyweight/day. The dosage of the compounds of the present invention may bedetermined by administering the compound to an animal and determiningthe plasma level of the active ingredient by known procedures.

[0097] The compound of the present invention can be formulated intopharmaceutical dosage forms using techniques well known in the art. Fororal administration, the compound can be formulated into solid or liquidpreparation such as capsules, pills, tablets, lozenges, melts, powders,suspensions or emulsions. For parenteral administration, the compound orits salts may be dissolved in a physiologically acceptablepharmaceutical carrier and administered as either a solution or asuspension. Illustrative of suitable pharmaceutical carriers are water,saline, dextrose solutions, fructose solutions, ethanol, or oils ofanimal, vegetable, or synthetic origin. The pharmaceutical carrier mayalso contain preservatives, buffers, etc. as are known in the art.

[0098] All cites to publications and patents herein are herebyincorporated by reference.

What is claimed is:
 1. A method of treating the behavioral,psychological or motor symptoms of dementia by administering to apatient having dementia a therapeutically effective amount of(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol,or a pharmaceutically acceptable salt thereof; or a prodrug, itsstereoisomer or pharmaceutically acceptable salt thereof, wherein theprodrug is

wherein R is C₁-C₂₀ alkyl.
 2. The method of claim 1 wherein the symptomis a behavioral symptom.
 3. The method of claim 2 wherein the behavioralsymptom is aggression.
 4. The method of claim 2 wherein the behavioralsymptom is sleep disturbances.
 5. The method of claim 1 wherein thesymptoms are psychological symptoms.
 6. The method of claim 5 whereinthe psychological symptom is hallucinations.
 7. The method of claim 5wherein the psychological symptom is delusions.
 8. The method of claim 5wherein the psychological symptom is depression.
 9. The method of claim1 wherein the symptom is a motor symptom.
 10. The method of claim 1wherein the dementia is Lewy body dementia.
 11. The method of claim 1wherein the dementia is Alzheimer's disease.
 12. The method of claim 2wherein the dementia is dementia in Parkinson's disease.
 13. The methodof claim 1 wherein R is C₅-C₂₀.
 14. The method of claim 1 wherein R isCg.
 15. The method of claim 1 wherein a therapeutically effective amountof(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanolor a pharmaceutically acceptable salt thereof is administered to thepatient.
 16. The method of claim 1 wherein a therapeutically effectiveamount of the prodrug, its stereoisomer or a pharmaceutically acceptablesalt thereof is administered to the patient.
 17. A method of treatingdopamine induced psychosis by administering to a patient having dopamineinduced psychosis a therapeutically effective amount of(+)-α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenyl)ethyl]-4-piperidinemethanol,or a pharmaceutically acceptable salt thereof; or a prodrug, itsstereoisomer or pharmaceutically acceptable salt thereof, wherein theprodrug is

wherein R is C₁-C₂₀ alkyl.
 18. The method of claim 17 wherein R isC₅-C₂₀.
 19. The method of claim 17 wherein R is C₉.